Method of controlling weeds



United States Patent 3,393,994 METHOD OF CONTROLLING WEED Nancy E.Achufi, Oreland, Pa., and Thomas F. Wood,

Wayne, N.J., assignors, by direct and mesne assignments, to GivaudanCorporation, Clifton, N.J., a corporation of New Jersey No Drawing.Filed Sept. 28, 1964, Ser. No. 399,904

7 Claims. (Cl. 71-123) ABSTRACT OF THE DISCLOSURE A new class ofherbicides is disclosed. The active compounds are acyl indans having thestructure:

wherein R is selected from the group consisting of hydro gen and alkylradicals of from 1 to 3 total carbon atoms with the proviso that atleast one of the R s is hydrogen, and wherein R is selected from thegroup consisting of hydrogen, alkyl radicals of from 1 to 6 total carbonatoms, acyl radicals and cyclo-alkyl radicals, with the proviso that atleast one of the R radicals must be an acyl radical.

Herbicidal test data on a large number of compounds are given in 61examples.

This invention relates to the use of certain compounds for purposes ofcontrolling weeds. More particularly, the invention relates to the useof acyl indane compounds having the structure:

wherein R is selected from the group consisting of hydrogen and alkylradicals of from 1 to 3 total carbon atoms with the proviso that atleast one of the R s is hydrogen, and wherein R is selected from thegroup consisting of hydrogen, alkyl radicals of from 1 to 6 total carbonatoms, acyl radicals and cyclo-alkyl radicals, with the proviso that atleast one of the R radicals must be an acyl radical.

The acyl indane compounds of the present invention have been found topossess high levels of herbicidal activity and are useful in controllingundesirable plants of both the monocotyledonous and dicotyledonousspecies on a preemergence basis. It has also been discovered that thecompounds of the present invention possess high rates of herbicidalactivity on both emerged and submerged aquatic weed species.

By the term pm-emergence is meant that the com- Patented July 23, 1968ICC of at least two types of common weed varieties from the class ofwild oats (Avena fatua), cheatgrass (Bromus secalinus), foxtail (Setariafaberii), barnyard grass (Echinochloa crusgalli), crabgrass (Digital-inischaemu'm), nut grass (Cypems esculentus), Johnson grass (Sorghumhalepense), curled dock (Rumex :crispus), yellow rocket (Barbareavulgaris), chickweed (Stellariai media), pigweed (Amaranthusrefroflexus), velvet leaf (Abu'filon theophmsti) and lambsquarter(Chenopodium album) were planted in soil under greenhouse conditions.Immediately after planting, the soil surface was sprayed with aqueoussolutions or suspensions of these compounds so as to apply theequivalent of 16 lbs. of the compound under test per acre of soilsurface. The aqueous solutions or suspensions were produced by stirringacetone and/ or alcohol solutions of these compounds into water. Threeweeks after spray application the herbicidal activity of these compoundswas determined in comparison with untreated control areas. The observedactivity is reported in the following table wherein the average activityrating on two or more of the weed varieties included in the tests isreported as the percent control of growth.

TABLE I Percent Example No. Compound Total Control of Weeds 1 Cheek 0 21,l,4,7-tetramethyl-5-1ndanylmethylke- 0116. 3-..1,353,4,6-tetramethyl-5-indanylrnethylkeone. 41,1,2,4,fi-pentamethyl-fi-indanylmethylke- 100 tone. 51,1,4,6,7-pentamethyl-5-indanylmethylke- 100 ne. 61,1-dtrnethyl-4,7-diethyl-fi-indanylmethyl- 100 ketone. 71,l-dirnethyl-4,6,7-triethyl-5indanyl- 100 methylketone. 81,k2,4-tetramethyl-5-indanylmethy1ke- 100 0110. 91,1,4-trimethyl-7-isopropyl-fidndanyl- 100 methylketone. 101,4-dimethyl-1-ethyl-7-is0propyl-6indanyl- 100 methylketone.1,1,4-trimethyl-fi-isopropyl-5-indanyl- 100 methylketone. 12-1,1,4,5-tetralnethyl-7isopropyl-6-l1ndanyl- 100 methylketone. 13-1,1,2-trimethyl-6-isopropy1-4-indany1- 100 methylketone. 141,1,4,6tetramethyl-7-isopropyl-5-indanyl- 95 methylketone. 15-1,1,4,7-tetramethyl-fi-isopropyl-5-lndanyl- 100 methylketone. 161,l-dimethyl-4-ethyl-7-isopropy1-5-in- 100 danylmethylketone. 17-1,l-dimethy1-4,6-diisop1opy1-5-indan3 l- 100 methylketone. 18.1,1-dimethyM,6,7-triisopropyl-S-indanyl- 100 methylketone. 19-1,1,4,6-tetrarnethyl-5-indanylethylketone. 100 20 1,1,4,7-tetramethyl-tindanylethylketone. 100 21. 1,1,6-trimethyI-S-indanylmethylkatone. 45 221,Ldimethyl-4,ddiisopropyl-dindanyl- 100 ethylketone. 231,1,4,7-tetramethyl-6-indanyl-n-pr0pylke- 95 tone. 241,l,4,6-tetramethy1-5-indanyl-i-propylke- 100 tone. 251,1,4,7-tetramethyl-5-indany1-i-propylke- 100 tone. 261,1,4,7-tetramethyl-fi-indanyl-i-propylke- 100 tone.1,1-dimethyl-4,6-diisopropyl-5-indanyl-i- 100 propylketone. 281,1,4,6-tetrarnethyl-5-indanyl-n-propylke- 100 tone. 291,1-dimethyl-4,6-diisopropyl-5-indanyl-n- 100 propylketone. 301,1,4,7-tetrarnethyl-Frindanylmethylke- 95 tone. 311,4-dirnethyl-1-ethyl-7-isopropyl-5-in- 100 danylrnethylketone. 321,1,4,7-tetramethyl-5-indany1ethylketone. 100 331,lzj,6-tetramethyl-indanylmethylke- 95 TABLE I--Continued PercentExample N0. Compound Total Control of Weeds 341,1,5,6-tetramethyl-4-indanylethylkctono. 100 35.1,1,5,G-tetramethyl-4-indanyl-n-propylke- 95 tone. 361,165,6-tetramothyl-4indanylisopropylke- 95 one. 37l,l,2,5,6-pentamethyl-4-indanylmethylke- 100 tone. 381,1-dimethyl-6-isopr0pyl-4-indanylmethyl- 95 etone. 391,1-dimethyl-fi-isopropyl-i-indanylethylko- 100 tone. 40.".1,l-dimethyl-fi-isopropyll-indanyl-n- 90 propylketone. 411,l-dimethyl-G-isopropyl-i-indanylisopro- 100 pylketone. 421,1,4,6,7-pentamethyl-S-indanylethylke- 100 tone. 431,1,4,6,7-pentamethyl--indanyl-n-propyl- 100 ketone. 441,1,4,6,7-pentamethyl-5-indanylisopropyl- 100 etone.1,l-dimethyl-4-ethyl-5-indanylmethylke- 100 tone. 461,1,G-trimethyl-4-ethyl-5-indanylmethyl- 100 ketone. 471,1dimethyl-4,6diisopropyl-7-indanyl- 100 ethylketone. 47a1,1,2,3,4,6-hexamethyl-5-indanylcyclohexyl- 90 stone. 47b1,1,2,3,3,7-hexamethyl-5-cyclohexyl-6-in- 90 danyl-n-amyllretone.

For practical use as herbicides, the compounds of this invention may beformulated with conventional agricultural carriers to obtain the desiredconcentration and to facilitate handling. For example, these compoundsmay be formulated into dusts by combining them with such materials astalc or clays. Wettable powder formulations may be obtained by adding adispersing or suspending agent to the dust formulations referred toabove.

If desired, the compounds of this invention may be applied as spraysolutions which can be prepared by dissolving the compounds in suitablesolvents, such as water, xylene, methylated naphthalenes, kerosenes,common agricultural oils, etc., in accordance with well establishedagricultural practices. The choice of solvent to be used will bedictated by the solubility of the compound sought to be sprayed in thatparticular solvent system. Generally, it has been found that themajority of these compounds have a relatively low order of watersolubility, so that the use of common agricultural organic solvents isthe preferred practice.

The com-pounds of this invention may also be emulsified or suspended inwater by adding wettng agents or emulsifying agents to aqueous systemscontaining one or more of the chemical compounds falling under thisdisclosure. These emulsified formulations are suitable for use inspraying directly upon the locus sought to be protected from undesirablevegetation. So far as has been determined no significant difference ineffect is realized from the use of aqueous emulsified formulations orfrom organic solvent solutions of these herbicides, providing, ofcourse, that a similar amount of chemical is employed in each instanceof use.

So far as concerns the amount of herbicide to be used, this is, ofcourse, subject to such considerations as the type of treatment to bemade, the area to be treated, the type of weeds sought to be controlledand the stage of development of the species being sprayed. Generally,however, concentrated herbicidal compositions of the present inventionare prepared so as to contain from 5 to about 60% of the activeherbicidal component, Compositions which are suitable for as isapplication generally contain from 0.1% to about of active herbicidalcomponent.

Preferred compounds of this invention, being highly active herbicides,may be used at relatively low concentrations as may be seen from thefollowing results:

4 EXAMPLE 48 A water-ethanol solution of1,1-dimethyl-4,6-diisopropyl-S-indanylmethylketone was sprayed over soilwhich was freshly sown to crabgrass (Digitaria ischaemum), ryegrass(Lolium perenne), barnyard grass (Echinochloa crusgalli), Johnson grass(Sorghum halepense), witchgrass (Panicum capillare), cheat grass (Bromussecalinus), Wild oats (Avena fatua) and foxtail (Setaria faberii) seeds.Spraying was effected at a rate equivalent to 3 lbs. of the activeherbicidal agent per acre of soil surface. Approximately 2 /2 Weeksafter s raying, an inspection of the treated area showed to 100% controlof these undesirable grass species as compared to untreated areas.

EXAMPLE 49 1,1-dimethy1-4-ethyl 7 isopropyl 5 indanylmethylketone,dissolved in a methylated naphthalene-alcohol solution, was sprayed oversoil which had been sown to wild oats (Avena fatua), crabgrass(Digitaria ischaemum), barnyard grass (Echinochloa crusgalli) andfoxtail (Seraria faberii) at such a rate so as to apply the equivalentof 4 lbs. of the herbicidal agent per acre of soil surface. Three weeksafter spray application the treated area was inspected and from 90 to100% control was observed for these weed species as compared tountreated areas.

EXAMPLE 50 An aqueous oil emulsion of1,1-dimethyl-4,6-diisopropyl-S-indanylethylketone was sprayed over soilwhich had been sown to Wild Oats (Avena fafua), crabgrass (Digitariaischaemum), foxtail (Setaria faberii), barnyard grass (Echinochloacrusgalli) and cheat grass (Bromus secalinus). Spraying was effected soas to apply the equivalent of 4 lbs. of the chemical compound per acreof soil surface, and at the time of spraying there were no plantsgrowing within the treated area. Approximately 3 weeks after sprayapplication an inspection of the treated area revealed that from tocontrol was obtained over undesirable plant species in comparison withuntreated or control areas.

EXAMPLE 51 Field plots were planted with both rice and barnyard grass(Echinochloa crusgalli) seeds and were immediately sprayed with aqueoussuspensions of 1,1-dimethyl-4,6-' diisopropyl-S-indanylethylketone at arate comparable to 3 pounds of the active chemical agent per acre ofsoil surface. Approximately 12 weeks after spraying an inspection of thetreated area showed that 95% control had been obtained over the barnyardgrass with no noticeable injury to the rice crop.

EXAMPLE 52 Field plots of transplanted paddy rice were seeded withbarnyard grass (Echinochloa crusgalli) and were then sprayed withaqueous emulsions of 1,l-dimethyl-4,6- diisopropyl-S-indanylethylketoneso as to yield an application rate comparable to 2 pounds of the activechemical agent per acre of soil surface. The rice plants wereapproximately eight inches in height at the time of spraying and many ofthem had 3 to 4 inch tillers. Seven weeks after application of thechemical herbicide an inspection of the treated plots showed 100%control over barnyard grass (Echinochloa crusgalli) with no noticeableinjury to the rice plants.

If it is desired to effect substantially complete elimination ofvegetation through use of one or more compounds of this invention, it isthen necessary to apply a higher rate of the chemical agent, for examplefrom 20 to 40 lbs/acre thereof, so as to obtain substantial soilsterilization.

Effective aquatic weed control can be accomplished by very lowconcentrations of the herbicidal compounds of the present invention asmay be demonstrated by the following results:

EXAMPLE 5 3 The following compounds were each applied to water whereinthere was growing emerged aquatic weeds of the water fern (Salviniarotundifolia) species. Each of the compounds was applied so as to obtaina rate of parts of the active chemical agent per 1 million parts ofwater:

Compound A1,l,4,7-tetramethyl-6-isopropyl-5- indanylmethylketone.

Compound B-1,1,4,5-tetramethyl-7-isopropyl-6- indanylmethylketone.

Compound C--l,l,4,6,7-pentamethyl-5-indanylmethylketone.

Compound D-1,l-dimethyl-6-isopropyl-4-indanylmethylketone.

Compound E1,l,5,6-tetramethyl-4-indanylethylketone.

Compound F1,1,4,6-tetramethyl-S-indanylethylketone.

Compound G-l,1,4,7-tetramethyl-5-indanylethylketone.

Approximately three Weeks after introducing the compounds to the aqueoussystems containing the water fern plants, an inspection revealed thatfrom 90 to 100% control was being obtained over the weed species.

Example 54 A rate of 10 parts ofl,1,6-trimethyl-4-ethyl-5-indanylmethylketone was added to each millionparts of Water wherein there was growing submerged aquatic weeds of thespecies Elodea canadensis.

Three weeks after adding this compound to the water an inspectionrevealed that 90% control over the undesirable aquatic Weed had beenobtained.

The compounds found to be suitable for use in the present invention maybe prepared by condensation of a hydrocarbon with a diolefin to form adesired indan followed by acetylation of the indan to yield the acylindanes falling within the scope of this disclosure. While thepreparation of these acyl indanes forms no part of the presentinvention, and such preparation may be accomplished by various methods,there are presented below illustrations of specific preparations ofcompounds falling within the scope of this invention.

Example 55.-Preparation of 1,1,4,6,7-pentamethyl-5- indanylmethylketone(Compound No. 5 in Table I) A solution of 68 parts of isoprene and 118parts of 1,2,4-trimethylbenzene was added slowly to an admixture of 400parts of l,2,4trimethylbenzene and 185 parts of 93% H 80 The additionwas continued for 4 to 5 hours at -6 to 0 C. After completion of theaddition, the lower acid layer was separated and the oil layer waswashed with dilute NaOH and dilute NaHCO solutions. Unreacted1,2,4-trimethylbenzene was recovered by distillation, and 132 parts ofl,l,4,6,7-pentamethylindan were recovered by reduced pressuredistillation.

94 parts of the 1,1,4,6,7-pentamethylindan thus produced were dissolvedin 150 mls. of CCL; and the solution was added slowly to an admixture of80 parts of anhydrous AlCl and 48 parts of acetyl chloride in 500 mls.of CCL at a temperature of 1 to 3 C. The addition was continued for 2 to3 hours after which the reaction mixture was poured over ice. Aftersettling, the lower CCL layer was separated and washed with water andwith dilute NaHCO solution. Upon removal of the CCL solvent a crudeproduct (137 parts) was recovered. Recrystallization was effected fromethanol to yield the desired product melting at 64-6-5 C.

Example 56.-Preparation of1,1-dimethyl-4,6-diisopropyl-S-indanylmethylketone (Compound No. 17 inTable I) A solution of 150 parts of isoprene and 200 parts ofdiisopropylbenzene was added slowly to an admixture of 400 parts of 93%H 50 and 1000 parts of diisopropylbenzene. The addition was continuedfor the same time and temperature as specified in the foregoingpreparation, and separation and recovery of the product was effected inthe same manner, resulting in 314 parts of4,6-diisopropyl-1,1-dimethylindan.

The 4,6-diisopropyl-1,1-dimethylindan was acetylated following the sameprocedure as specified above, with the exception that ethylenedichloride was used in lieu of CCL 690 parts of the indan yielded 637parts of a crystalline product, after vacuum distillation, which meltedat 74-75 C.

Example 57.-Preparation ofl,1-dimethyl-4,6-diisopropyl-S-indanylethylketone (Compound No. 22 inTable I) 4,6-diisopropyl-l,l-dimethylindan, as prepared in Example 56above, was reacted with propionyl chloride utilizing the acylationtechnique described above in Example 55 with the exception that ethylenedichloride was substituted for carbon tetrachloride. From 575 grams ofthe hydrocarbon there was obtained 636 grams of vacuum distilled1,1-dimethyl-4,6-diisopropyl-5-indanylethylketone having a boiling pointof 132-133" C. at 2 mm. After distillation this ketone solidified to awhite, waxy product having a congealing point of 84 C. and a meltingpoint of 88 C. Crystallization from methanol yielded a white powdermelting at 78-88 C. Analysis by vapor-phase chromatography showed thepresence of two isomers. The isometric mixture was subjected tochromatographic resolution to separate the isomers. The major componentwas obtained in 98% purity and melted at 1l6-118 C. The minor componentwas obtained in 96% purity and melted at 92-94" C.

Based on infrared and NMR studies the higher melting isomer was assignedthe structure 1,1-dimethyl-4,6-diisopropyl-S-indanyl-ethylketone. Thelower melting isomer was identified as1,1-dimethyl-4,6-diisopropyl-7-indanylethylketone.

Example 58.-Preparation of 1,4-dimethyl-1-ethyl-7-isopropyl=5-indanylmethylketone (Compound No. 31 in Table I)3-methyl-1-penten-3-ol was dehydrated by the procedure of US. Patent2,381,148 to produce a mixture of 3-methyl-l,3-pentadiene and2-ethyl-l,3-butadiene, boiling point of 1l4118 C. Cyclo-additi'on ofthis mixture to p-cymene following the general diolefin-hydrocarboncondensation procedure, as illustrated in Examples 55 and 56, produced1,4-dimethyl-l-ethyl-7-isopropylindan, a colorless liquid having aboiling point of 913-98 C. and an n of 1.5146. The indan hydrocarbonderivative thus produced was aeetylated by the general method of Example55 to produce the ketone derivative 1,4-dimethyl-1-ethyl7-isopropyl-5-indanylmethyl-ketone having a boiling point of137-139 C. at 2 mm. and an ri of 1.5336.

Example 59.Preparation of 4,6-dimethyl-5- indanylmethylketone5,7-dimethyl-1-indanone was prepared by the combination.acylation-alkylation reaction between meta xylene and B-chloropropionylchloride using the general procedure described by Hart and Tebbe (J. Am.Chem. Soc., 72, 3286 (1950) in their preparation of 4,7-dimethyl-1-indanone from para xylene. The ketone was obtained as a colorless solid,M.P. 76-79".

The ketone was reduced by the Wolff-Kishner method (Huang-Minlonmodification) using hydrazine hydrate, diethylene glycol solvent andcaustic soda flakes to produce the corresponding hydrocarbon,4,6-dimethylindan, a colorless liquid, B.P. 61 (2 mm), 11 1.5325.

Acetylation of the above hydrocarbon by the method of Example 55, usingethylene dichloride solvent, gave a 95% yield of4,6-dimethyl-5-indany1methylketone, a colorless liquid, B.P. 106 (2mm.), n 1.5459. This ketone showed activity as a pre-emergenceherbicide.

Example 60.Preparation of 4,6,7- trimethyl-S-indanylmethylketone Insimilar fashion, starting with pseudocumene (1,2,4- trimethyl-benzene),the following compounds were prepared:

(a) 4,5,7-trimethyl-l-indanone, a colorless solid, M.P.

(b) 4,5,7-trimethylindan, a colorless material, B.P. 79 (1 mm.), whichsolidified immediately after distillation, M.P. 4647.

(c) 4,5,7-trimethyl-6-indanylmethylketone, a colorless solid, M.P. 62-64(from methanol). This compound was active as a pre-emergence herbicide.

Example 61.Preparation of 6-isop'ropyl-1,1,4- trimethyl-S-indanealdehyde(a) 5-chl0romethyl-6-is0pr0pyl-1,1,4-trimethylindan. A mixture of 28 g.of zinc chloride, 41.5 g. of paraformaldehyde and 202 g. of6-isopropyl-1,1,4-trimethylindan was heated with stirring to 65 C. anddry hydrogen chloride was passed into the mixture during one hour and 40minutes at 6575 C. There was consumed 56 g. of hydrogen chloride.

The solution was cooled to 30 C. and the lower layer, 58 g., separatedand the upper layer stirred minutes with 18 g. of sodium bicarbonate.The solution was filtered and the filtrate vacuum-distilled in thepresence of 2 g. of anhydrous soda ash. There was collected, in additionto 64 g. of recovered 6-isopropyl-1,1,4-trimethylindan, 143 g. of5-chloromethyl-6-isopropyl-1,1,4-trimethylindan as a colorless oilboiling at 112 C./0.5 mm. Hg; n 1.5375.

(b) 5-)0rmyl-6-is0pr0pyl-1,1,4-trimethylindan.A mixture of 135 g. of5-chloromethyl-6-isopropyl-1,1,4-trimethylindan, 261 g. of acetic acid,175 g. of Water and 244 g. of hexamethylene tetramine was refluxed for 3hours with agitation.

261 g. of 37% hydrochloric acid was added and the solution refluxed for45 min. with agitation. The mixture was cooled and the oil whichseparated was taken up in benzene and washed neutral. After removal ofbenzene by distillation the remaining oil was fractioned through 878.5-80.1 C. The product has a musk odor and is effective as apre-emergence herbicide showing a high degree of selectivity.

In a similar manner, various other compounds falling within the scope ofthis invention may be prepared. It has been found that herbicidalactivity is demonstrated by products recovered by vacuum distillation,and that further purification of the compounds is not required.

What is claimed is:

1. A method of controlling weeds comprising applying to the locus to beprotected a herbicidally effective amount of a compound of the formula:

wherein R ie selected from the group consisting of hydrogen and alkylgroups of from 1 to 3 total carbon atoms with the proviso that at leastone of the R groups is hydrogen; and wherein R is selected from thegroup consisting of hydrogen, alkyl groups of from 1 to 6 total carbonatoms and lower alkanoyl groups, with the proviso that one of the Rgroups must be a lower alkanoyl group, and at least one R group must bean alkyl group, with the further proviso that where only one R is alkylit has from 1 to 3 carbon atoms.

2. The method of claim 1 wherein the compounds is1,1-dimethyl-4,6-diisopropyl-S-indanylethylketone.

3. The method of claim 1 wherein the compound is1,1-dimethyl-4,6-diisopropyl-7-indanylethylketone.

4; The method of claim 1 wherein the compound1,1,6-trimethyl-4-ethyl-5-indanylmethylketone.

5. The method of claim 1 wherein the compound1,1,2,4,6-pentamethyl-5-indanylmethylketone.

6. The method of claim 1 wherein the compound is1,1,4,6-tetramethyl-S-indanylethylketone.

7. The method of claim 1 wherein the compound is1,1-dimethyl-4,6-diisopropyl-5-indanylisopropylketone.

References Cited UNITED STATES PATENTS 3,152,192 10/1964 Wood et al260-668 3,240,829 3/1966 Wood et al. 260668 FOREIGN PATENTS 796,1296/1958 Great Britain.

LEWIS GOTTS, Primary Examiner.

G. HOLLRAH, Assistant Examiner.

UNITED STATES PKTENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,395,994 July 23, 1968 Nancy E. Achuff et al.

It is certified that error appears in the above identified patent andthat said Letters Patent are hereby orr as shown below:

Column 3 line 50 "wettng" should read wetting Column 8, lines 21 and 25,after "consisting", each occurrence, insert essentially line 21, ie"should read i's same column 8, lines 12 to 20, in the structuralformula, in the aromatic ring, "R should read R Signed and sealed this20th day of January 1970.

(SEAL) Attest:

Edward M. Fletcher, Jr.

Attesting Officer Commissioner of Patents WILLIAM E. SCHUYLER, JR. 1

